The Celtics felt they had a chance taken from them against the Miami Heat last spring.

Now they have a chance to take it back starting in Game 1 of the Eastern Conference finals in Miami tonight.

Down 2-0 in last year’s conference semifinals, the Celtics were still confident. They’d won the regular season series against LeBron James, Dwyane Wade and Co., and felt if they could exploit matchups inside and at point guard, and protect homecourt, there was no reason they couldn’t steal one in South Beach and win the playoff series as well.

It was unfolding exactly as they had hoped when they had a 10-point lead, amid a 16-4 run, in the third quarter of Game 3. But then they watched as their chance at an upset got ripped apart when Wade pulled Rajon Rondo to the parquet on a play that dislocated the point guard’s left elbow.

Rondo somehow returned after the grotesque injury, but was never the same in the series. Kevin Garnett scored 28 points with 18 rebounds in a 97-81 triumph that night, but his play faded the rest of the way as well.

Still, the Celtics had a chance to win Game 4 on a last-second shot in regulation when a badly botched play led to a Paul Pierce miss and an overtime Heat victory. And in Game 5, the Celtics had a 13-point lead in the second half of Game 5 in Miami before a ferocious James-led run delivered the knockout blow.

Celtics coach Doc Rivers later said that exit was, in many ways, harder on the players than the Game 7 loss to the Lakers in the 2010 NBA Finals.

Now, after Saturday night’s Game 7 victory over the Philadelphia 76ers propelled the Celtics to their third conference finals appearance in five years, they have their sorely-sought shot at redemption.

“This is a good time right now,” Garnett said. “This is the cream of the cream. This is what it’s all about – conference finals. We didn’t like the way we left last year, soo we’ll see what happens, man. We’ll see what happens. Let’s get it on.”

Because the Celtics had such trouble putting away the upstart 76ers, they had precious little time to prepare for the next challenge. Rivers said he defied superstition and packed for Miami in advance of Game 7 so he could spend the wee hours of yesterday morning watching film. The team met for another film and strategy session later yesterday and boarded the three-hour flight to Miami.

The coach said the team would not practice yesterday, and will only walk through a morning shootaround today, in hopes of staying as fresh as possible for tonight.

Although the Heat will have had the luxury of three days off to wait for Boston, Pierce said he doesn’t mind the spot the Celtics are in for Game 1.

Page 2 of 2 - “I kind of like it this way,” he said. “It keeps us in rhythm. It keeps us playing. We’re an older team, so we don’t want to sit around for too long. We like the fact that we usually go right into it.”

The captain may like it a little more than Garnett, but after his 18-point, 13-rebound effort in 37 minutes in Game 7 he wasn’t about to lament the lack of downtime.

“We don’t have any other options,” he said. “We’re not going to use that as an excuse. We’ve played this team before. If you’ve been watching basketball, and watching their series, you know how they’ve been playing. I think D-Wade and LeBron have been putting up 65, 70 points, collectively. We definitely have to slow that down.

“We have some things we want to do. And we’re prepared for that. These are the cards we were dealt. We’re going to play them.”

The Celtics felt they had a winning hand last year too, before they were cut off at the elbow. This year, through Avery Bradley’s shoulder, Ray Allen’s ankle, Jermaine O’Neal’s wrist and the hearts of Jeff Green and Chris Wilcox, they’ve taken more than their share of hits again.

But after beating Miami three times in the final month of the regular season – albeit once in the last week with the JV squads playing for each side – they believe they not only can stay with the Heat, but they can take them out and extend the new Big 3 era into one more NBA Finals.

“We feel we can beat Miami,” Rondo said. “Obviously, we got to this point. There’s no doubt in my mind.”

(Scott Souza can be reached at 781-398-8006 or ssouza@wickedlocal.com. Follow him on Twitter @scott_souza.)